Specific Aim 3: To evaluate the effects of CM on hypothesized mediators of the MET/CBT and the FFT intervention effects. The investigators anticipate that the CM conditions are more likely than the nonCM conditions to accelerate the adolescent's motivation (1) to achieve abstinence, (2) to attend and participate in treatment, (3) to complete homework assignments. The SOCRATES scale will assess their motivation to achieve abstinence. Specifically, the investigators predict that youth receiving the CM versus nonCM will show higher rates of motivation for change at the 2-month assessment (Hypothesis 3a) and higher rates of treatment attendance and homework compliance (as measured by weekly therapist reports) over the course of treatment (Hypothesis 3b).